Marketable Securities (Details 2) (USD $) In Thousands	Oct. 02, 2011	Apr. 03, 2011
Schedule of Unrealized Losses by Investment Category
Fair value of less than 12 months	$ 139,109	$ 96,164
Unrealized losses of less than 12 months	(985)	(560)
Fair Value of 12 months or greater	186	0
Unrealized losses of 12 months or Greater	(4)	0
Fair value, Total	139,295	96,164
Unrealized losses, Total	(989)	(560)
U.S. Government and agency securities [Member]
Schedule of Unrealized Losses by Investment Category
Fair value of less than 12 months	27,057	25,712
Unrealized losses of less than 12 months	(32)	(216)
Fair Value of 12 months or greater	0	0
Unrealized losses of 12 months or Greater	0	0
Fair value, Total	27,057	25,712
Unrealized losses, Total	(32)	(216)
Corporate debt obligations [Member]
Schedule of Unrealized Losses by Investment Category
Fair value of less than 12 months	96,436	60,595
Unrealized losses of less than 12 months	(872)	(282)
Fair Value of 12 months or greater	0	0
Unrealized losses of 12 months or Greater	0	0
Fair value, Total	96,436	60,595
Unrealized losses, Total	(872)	(282)
Asset and mortgage-backed securities [Member]
Schedule of Unrealized Losses by Investment Category
Fair value of less than 12 months	12,758	7,991
Unrealized losses of less than 12 months	(76)	(52)
Fair Value of 12 months or greater	186	0
Unrealized losses of 12 months or Greater	(4)	0
Fair value, Total	12,944	7,991
Unrealized losses, Total	(80)	(52)
Municipal bonds [Member]
Schedule of Unrealized Losses by Investment Category
Fair value of less than 12 months	2,858	1,866
Unrealized losses of less than 12 months	(5)	(10)
Fair Value of 12 months or greater	0	0
Unrealized losses of 12 months or Greater	0	0
Fair value, Total	2,858	1,866
Unrealized losses, Total	$ (5)	$ (10)

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